Data storage and retrieval systems are used to store information provided by one or more host computer systems. Such data storage and retrieval systems receive requests to write information to a plurality of data storage devices, and requests to retrieve information from that plurality of data storage devices. Upon receipt of a read request, the system recalls information from the plurality of data storage devices, and optionally moves that information to a data cache. Thus, the system is continuously moving information to and from a plurality of data storage devices, and optionally to and from a data cache.
It is known in the art to configure the plurality of data storage devices to form a storage array. It is further known to write information to such a storage array using a number of RAID protocols.
In order to reduce the physical size and/or cost of the data storage and retrieval system, what is needed is a data storage and retrieval system wherein the plurality of data storage devices comprises two or more data storage device assemblies, wherein each of those assemblies comprises two or more data storage devices. What is further needed is a method to reconfigure a data storage array comprising a plurality of data storage device assemblies upon the failure of a data storage device disposed in one of those data storage device assemblies.